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How To Create Table with Identity Column
...ues ('NULL','address2')
insert into teppp ( addresss) values ('address3')
select * from teppp
null string , address1
NULL,address2
NULL,address3
If you try inserting same values as below:
insert into teppp ( name,addresss) values ('','address4')
insert into teppp ( name,addresss) values ('NULL',...
Why does C# not provide the C++ style 'friend' keyword? [closed]
...ly.
Typically, a designer desires to expose only a few private methods to selected few other classes. For example, in a class factory pattern it may be desired that class C1 is instantiated only by class factory CF1. Therefore class C1 may have a protected constructor and a friend class factory C...
Is there a NumPy function to return the first index of something in an array?
...st element. Note also that where and nonzero return arrays, so you need to select the first element to get the index.
In [71]: np.argmax(a==2)
Out[71]: 2
In [72]: np.where(a==2)
Out[72]: (array([2], dtype=int64),)
In [73]: np.nonzero(a==2)
Out[73]: (array([2], dtype=int64),)
Time comparison
Ju...
Why should hash functions use a prime number modulus?
...er of buckets. This is convenient and saves having to search around or pre-select a prime number of the right magnitude. So you rely on the hash function not to use even multipliers, which is generally a safe assumption. But you can still get occasional bad hashing behaviours based on hash functions...
Add MIME mapping in web.config for IIS Express
...ble-click the "MIME Types" configuration option while having IIS root node selected in the left panel and click "Add..." link in the Actions panel on the right. This will bring up the following dialog. Add .woff file extension and specify "application/x-font-woff" as the corresponding MIME type:
...
Use of var keyword in C#
...oing things like var customers = whatever; var query = from c in customers select stuff it doesn't matter what the exact type of 'customers' is. It's obvious how you can use it, and that's enough. And if the actual type is cumbersome, it's worthwhile to suppress it.
– Joren
...
Simple way to find if two different lists contain exactly the same elements?
...) because we are doing O(2*n) insertions into a hashmap and O(3*n) hashmap selects. I have not fully tested this code, so beware :)
//Returns true:
listsAreEquivelent(Arrays.asList("A","A","B"),Arrays.asList("B","A","A"));
listsAreEquivelent(null,null);
//Returns false:
listsAreEquivelent(Arrays.as...
How are zlib, gzip and zip related? What do they have in common and how are they different?
...ompressed output for the same input data, as evidenced by the existence of selectable compression levels that allow trading off compression effectiveness for CPU time. zlib and PKZIP are not the only implementations of deflate compression and decompression. Both the 7-Zip archiving utility and Googl...
How do I add a ToolTip to a control?
...
Add a ToolTip component to your form
Select one of the controls that you want a tool tip for
Open the property grid (F4), in the list you will find a property called "ToolTip on toolTip1" (or something similar). Set the desired tooltip text on that property.
Rep...
Setting design time DataContext on a Window is giving a compiler error?
...w, where you can then scroll down to the ViewModel property, expand it and select the item that you want to bind to.
When you do all that, the VS designer will create a Binding statement whose path is relative to the View, i.e. it happens to be exactly the same as the path that x:Bind expects. So,...